[Interaction of bromophenol blue with serum albumin: criteria for using dyes for assessing the state and quantity of protein].
The optical properties of the complexes of the pH-dependent dye bromophenol blue (BPB) with human serum albumin were investigated by the spectrophotometric method. The solvatochromic longwave displacement of bound BPB-2 absorption and BPB-1/BPB-2 redistribution were shown to form the optical signal of complexes. Because of the distortion of the bound BPB-2 signal its quantity was determined as delta A630 = A630 - A660 and the use of lambda max as structural parameter was limited to low pH less than or equal to 3. The conclusion was made that BPB is inapplicable as a structural probe on account of low structural dependence of delta A630 and pH-limitation of lambda max used. The maximal absorption delta Amax = Amax - A660 and its structural independence were obtained in the region of 70-100% occupation of the dye-binding centers of the protein. It is the optimal conditions for the quantitative determination of protein. After maximal dye binding (15-16 molecules of BPB per 1 molecule of albumin) the aggregation and precipitation of the complexes occurred.
Gavrilov
V B
VB
Nikol'skaia
V P
VP
Kaler
G V
GV
Konev
S V
SV
D001978:Bromphenol Blue / Q000378:metabolism*; D006358:Hot Temperature; D006801:Humans; D006863:Hydrogen-Ion Concentration; D011489:Protein Denaturation; D012709:Serum Albumin / Q000378:metabolism*; D013056:Spectrophotometry, Ultraviolet
D012709:Serum Albumin; D001978:Bromphenol Blue
Vzaimodeĭstvie bromfenolovogo sinego s syvorotochnym al'buminom: kriterii ispol'zovaniia krasiteliia dliia otsenki sostoianiia i kolichestva belka.